If Croatia could have chosen the moment for its accession to the European Union, it would not be 1 July 2013. The Pew Research Centre has just published the results of polling conducted in eight EU member states. The most disturbing finding is that the percentage of citizens in favour of the European project has plummeted from 60% a year ago to 45% now. A failing economy, Europe's north-south divide and distrust of the political elite have led to such results.

Then there are the consequences of Romania and Bulgaria joining the EU in 2007 without adequate preparation. Disappointment with the two new members was followed by a more sceptical approach to further accessions. As it is, the EU has had enough problems with former communist countries, and now yet another one is joining. Yes, Croatia is smaller and perhaps better prepared, but enthusiasm is nevertheless lacking on both sides.

When the newly independent nation began the negotiation process, Croatians regarded the EU like a rich aunt. After all, they always thought of membership not as coming in but coming back. But even so, the nationalist opposition was fairly vocal. Why join a new community of states just after leaving Yugoslavia, and a bloody war that had cost thousands of lives? If the 1991-95 wars were for independence, then why give up that newly won political sovereignty? And what about the Croatian national identity that had been reinvented and celebrated with so much energy by the first president, Franjo Tudjman? The most serious argument was that the whole region was too volatile.

However, the political elite at the time presented it in ideological terms: Croatia does not belong to the Balkans. The Balkans are the Others – Orthodox and Muslims, not Catholics. Joining the EU would reinforce the difference, and "draw the line" between them and us. This must be the only reason Croatia's Catholic church supported the yes vote in last year's referendum, when 66% voted to join the EU.

In later years, though, the important if not crucial argument about peace and stability was neglected more and more. Politicians of both right and left chose to perpetuate a rosy picture of economic benefits, investments, employment opportunities and so on. Yet with accession approaching, it became clear that this was not going to happen. The economic crisis in the EU coincided with negative results from the badly handled privatisation of state assets, with allegations of political corruption. The state bureaucracy is huge and no reform has touched it. Unemployment climbed to 20% and is still rising. Over half those unemployed are young people. In Europe, only Greece and Spain have worse jobless figures. The public debt is almost 60% of GDP. No wonder Germany fears Croatia is a future Greece.

Croatians themselves seem not to be in the mood to celebrate. In this last month before joining the EU, the media expressed anxiety, for instance about the likely competitiveness of our products – although our main industry, tourism, is doing well. One could sense an atmosphere of closing instead of opening, of fear instead of joy. When people are faced with uncertainty, they usually turn to traditional values of family and religion. Conservative civil organizations, backed by the Catholic church, held a referendum for to change in the constitution, demanding to that it define marriage as heterosexual. There is also uncertainty about how the new rules and regulations will operate.

The only people looking forward to joining the EU seem to be young people, who anticipate the possibilities of study and work abroad – there will be no more customs at our western borders, no more queueing up in non-EU queues for those who have money to shop and to travel.

It looks as if in the whole process of accession the most important elements were "lost in transition". Beyond Croatia being Europe's long-lost Catholic child, the fact is that the country was at war only two decades ago, and that peace and security should mean more to it than putative economic gains. Economic survival for this small and poor state would be even harder outside the union. This is why 1 July is a historic date, even if the actual moment of joining is really not the best one either for Croatia or for the EU.